Why would sending money to Her arouse you? You don't see the appeal, you don't understand why others get off to paying Her for no apparent reason.
Until you finally send, and you feel that thrill. It feels so good knowing you've pleased Her, knowing you've submitted to Her. It feels intense, automatic, it just seems to make sense.
Realizing everything belongs to Her, everything should be done to please Her. That you really would do anything for Her. That you want to dedicate yourself to making Her life easier and happier. Why wouldn't you? She is everything.
Then you wonder why it was ever even a question. Of course pleasing Her, in any way, would arouse you. It seems so obvious now. It was only natural for you to realize it. Her pleasure is what gives you pleasure.
And you're so excited to continue your journey deeper into Her control, to further Her happiness and pleasure as much as you can. You just can't wait to send again.